My favorite words occupy more thought-space than I'm readily willing to admit. Sometimes I worry that the words mean more to me than the things I associate them with... But hey--I'm drunk as fuck and it's a fresh day of the new year! This is no time for dialectic crises!
I say the word yikes a lot, that's an all-time classic. Just the way it feels, and the shape my face makes when I say it tells you everything about how I'm feeling. The 'y' at the beginning is fun, that 'yuh' sound is underrated. The hard 'k' at the end, it's just explosive and sounds nice and punchy. It's just an expression, it barely means anything. But the sound is just as important.
Rambunctious. I never use this word, but often I'll catch myself saying it so much in my head that it loses all meaning. Truthfully, most of my favorite words are chosen not because of their meaning, but because of the way it sounds, the twists my tongue gets to make and the shapes my mouth is allowed to form.